National Communication System
The NCS shall consist of the telecommunications assets of the entities represented on the NCS Committee of Principals and an administrative structure consisting of the Executive Agent, the NCS Committee of Principals and the Manager. The NCS Committee of Principals shall consist of representatives from those Federal departments, agencies or entities, designated by the President, which lease or own telecommunications facilities or services of significance to national security or emergency preparedness, and, to the extent permitted by law, other Executive entities which bear policy, regulatory or enforcement responsibilities of importance to national security or emergency preparedness telecommunications capabilities. (b) The mission of the NCS shall be to assist the President, the National Security Council, the Homeland Security Council, the Director of the Office of Science and Technology Policy and the Director of the Office of Management and Budget in: (1) the exercise of the telecommunications functions and responsibilities set forth in Section 2 of this Order; and (2) the coordination of the planning for and provision of national security and emergency preparedness communications for the Federal government under all circumstances, including crisis or emergency, attack, recovery and reconstitution.

Source:
Executive Order 12472 - Assignment of National Security and Emergency Preparedness Telecommunications Functions (amended by E.O. 13286 of February 28, 2003)